Proportioning device especially designed for carbureters.



Hl N. MOTSINGER.

PROPRTIONING DEVICE ESPECIALLY DESIGNED FOR CARBURETERS. APPLICATION man JAN.10. 19:3. RENEwED APA.21.1915.

L, Patented May25,1915..

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H. N. MOTSINGERV. PRoPonTloNlNG DEVICE ESPECIALLY DESIGNED FOR cARUREERs. APPLICATION FILED IAN-10|I9l3. RENEWED APR. 2l, I9I5. 1,14525, Patented May 25, 1915.

5 SHEETS-SHEET 2.

H. N. MOTSINGER.

PROPORTIONING DEVICE ESPECIALLY DESIGNED FOR CARBURETERS. APPLICATION F1150 JAN. 10, 1913. RENEwED APR.21, 1915.

1,140,525. Patented May 25, 1915.

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" .my 3. n

H. NI MOTSlNGERI PIIDPDRTIDIIIIIIG DEvIcE ESPECIALLY DESIGNED EDR cAIIDuIIETEIIs.

APPLICATION FILED .IAN- II |913- RENEWED APR. 2||19|5. 1 ,140,525. Patented May 25, 1915.

5 SHEETS-SHEET 4.

@Houma H. N. MOTSINGER.

PROPORTIONING DEVICE ESPECIALLY DESIGNED FOR CARBURETEHS. APPL1cAT1oN mso 11111.10. 1913. RENEwEn APR,21,1915.

1,140,525 Patented May 25, 1915.

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Homin N. ivro'is'rNGnR,V or LAFAYETTE; INDIANA.

PROPORTIONING DEVICE ESPECIALLY DESIGNED FOR CARBURETERS.

Application filed January 10, 1913,

To all whom t may concern:

Beit known that 1, HoMnn N. MoTsINGER, a citizen of the United States, residing at La Fayette, in the county of Tippecanoe and State of Indiana, have invented a new and useful Proportioning Device Especially Designed for Carbureters, of which the folllowingis a specification.

It has long'beenweli known that, under any particular atmospheric conditions a particular proportioning of air and a fuel gas,

' resulting from the evaporation or nebulization of a liquid hydrocarbon, will produce a better explosive or combustible mixture than some other proportioning, and it has also been recognized that the desirable proportioning, for any particular set of conditions, should remain the same irrespective of the volume of mixture used in any unit of time. It has also been recognized that varying weather conditions require variations in the amount of fuel'per unit of volume of air.

The object of my invention is to produce an apparatus by means of which twoflowing materials may be intermingled in exact and uniform proportions throughout the range of the apparatus and in which the proportion may be varied without interfering with the accuracy of proportionment throughout the range of the apparatus.

rlhe accompanying drawings illustrate my invention as embodied 'in a carbureter for internal combustion engines but it will be recognized that this single application is only one of many to which my -invention may be made.

Figure 1 is a sectional perspective of a carbureter embodying my invention; Fig. 2 a plan on a. smaller scale; Fig.3 a diagrammatic development 'of a properly formed throttling valve by means of which equal effective area increments of fiow orifice may be obtained by equal lifts of the throttling valve, said figure also showing some'approx imations thereto; Fig. 4f a diagram showing the generating line for the proper form of a valve whereV the total lift ofthe valve is equal to half its diameter; Fig. 5 a diagram used in the development of theformula for determining the shape ofthe throttling valve for any orifice diameter; Fig. 6 a section-on line (3e-6 of Fig. 2; Fig. 7 a diagramof a test apparatus for experimentally Calibrating the valves; Figs. 8, 9 and 10 diagrams ofl various means for'obtaining proper Specication of Letters Patent.

Patented May 25, 1915.

seria1No. 741,185. Renewed Aprnizi, 1915. seriai No. 22,944.

relative movements of the two valves; Fig. 11 a diagram illustrating the relationship between air and fuel inlet.

In the drawings, 10 indicates the main body of a carbureter provided with an air 1nlet"orifice 11, a fuel inlet orifice12, and an outlet passage 13. Arranged in the inlet orifice 11 is a throttling valve 1a which is preferably of such type as to be moved toward an open direction by the suction applied to the outlet passage 13. Valve 14 is provided with a stem 15 arranged to engage the free end of a lever 16 which, in a portion .of its length, is provided with an upwardly projected longitudinal knife-edge 17, upon which rests a knifeedge of a finger 18 which lies at right angles to lever 16. Finger 18 is carried'by a rod 19 mounted in suitable brackets 20 and is normally urged in one directionY by a spring 21, the rod 19 being moved in the opposite direction by any suitable connections 22 preferably extended to a point of convenient access as, for instance, the steering wheel of a motor car. Finger 18 is threaded on rod 19, as indicated in dotted lines in Fig. 1, so that the finger may be accurately adjusted longitudinally on the rod. f

Pivoted upon rod 19 between brackets 20 is a plate 23 which lies closely upon finger 18 but does not interfere with its lateral adjustment and this plate 23A carries a pair of fingers 25, 25 which straddle the stem 26 of a fuel valve 27 beneath the head 28 upon the stem 26. rlhe fuel valve 27 is urged toward closing position in the fuel inlet orifice 12 by aspring 29 and head 28 may be adjusted so that the valve 27 will always be closed when valve 14 is closed and lever 16 is in its.posi tion in which edge' 17 is parallel with the li-ne of adjustment of finger 18. Passage 31 leads from a point in front of valve 14, past nozzle (or orifice) 12,'and into alinement with passage 13, so that the :mixture issuing from passage 31 will intermingle with the air admitted through orifice 11 before passing through the outlet passage 13. Fuel is supplied to orifice 12 from a reservoir 35 in which the level of fuel is controlled by a fioat 35 acting to open a self-closing valve 37 arranged in the supply passage 88.

The exact shape desirable for the two valves 14 and 27 will be dependent upon the. shape ofthe orifices with which the valves are to 'cooperate but in any vcase each valve must `be especially and carefullyk contoured with 'relation to the orifice with which it is to cooperate in such manner that equallifts.

of the -valve with relation to the orifice will result substantially in equal increments to the edective orifice area, wholly irrespective of the particular point in the total travel of the valve where such lift is made' and irre.- spective of the amount of the unit llft so that if the total desired liftof the valve be divided into any given number of steps, then the total lift of the valve may be increased or diminished without changing the `simple arithmetically-progressive increments'to the effective orifice area. I'

As a circular orifice is the one most readily commercially formed, I shall show in detail the manner of determining theproper shape of a body of revolution which will co- .operate with said orifice to produce the result above defined- In the determination of this matter there are a number of factors that will influence the quantity of fuel which will be delivered in any given unit of time throughthe orifice (a) The differencein pressure between the two sides of the orifice.

() The area of the opening of the orifice, (c) T e amount of resistance offered to the passage of the fiowing material along the surfaces of the passageways, and by the eddy currents. (ai) yThe amount of contraction in the stream caused by the character of the channels leading to and away from the orifice.

In the case of a carbureter it is not necessary ,to consider the first variable above mentioned, because the suction can vary through a considerable range without materially'affecting the character ofthe mixture, provided the minimum vacuum maintained is sufficiently high, compared to the suction head which is necessary to start the gasolene fiow. The quantity of air and of fuel delivered will then be proportional to the square root of the suction head, A change in the su tion will, therefore, change the rate of delivering the mixture but will not materially change the proportion of fuel to air. This is readily determinedII from the equation:

where Wzweight of air delivered, A=area of the orice, :the constant of air from the equation P =RT, -P pressure, Pvzpressure in carbureter body, Ta: absolute temperature of the atmosphere.

In the above equation everything is a constant except PAPa Pv).

portion to the square root of the suction be determined -determined experimentally -in a manner A o. a carbureter the effective head causing a delivery of fuel is less than the suction head by the small amount that the delivery tube for fuel extends above. the fuel level in the float chamber. Compared to the total suction, this slight difference isnegligible, and the quantity of fuel delivered may be considered as varying as Wto. In this special design, however, the suction head re mains nearly constant from no load at low speed to full load at maximum speed, thus reducing errors due to the slight elevation of the fuel nozzle, to an entirely negligible quantity.

The exact effect produced by the items (c) and (d) above mentioned cannot readily mathematically but can be which I shall hereafter point out.

The primary problem presentedis a deterf mination of the exact shape necessary for the valve as compared with its orice and this can be determined mathematically. Supposing first a circular orifice 'to be throttled by a needle valve which is to be a body of revolution about an axis passingl through the center of the orifice and coaxial therewith. Referring now to Fig. 5, OL and OR indicates a circular orifice; VLPVR indicates a valve which is to be a solid of revol lution about the axis CP; MN indicates any circle parallel to the plane of the orifice and' in the surface of the valve; OLM indicates the section of the surface of minimum area which will-close the orifice between the circles OLOR and MN If now it be assumed that the circle MN moves from P to VLRR in such a way that it is always parallel to the plane of the orifice, and so that the minimum surface closing the opening between vMN and LOR is a constant and equal to the area of the orifice, then VLMPNVR will be the surface formed by MN in this movement. Let QLMNQR to the surface VLPVR not cutting VLVR at valve QLMNQR will contains the circle points lies beyond the surface VLMPNVRQ Referring 'now to Fig. 8, let OLOR be a circular orifice and assume that the valve is fixed in position and that the orifice take the successive positions 2, et, 6, etc., such posi-V tions being equal advancements of the orifice relative to the valve.

Let A=the area ofthev orifice; Lzthe equal any other valve tangent MN, but at all other Ln=the lift of the entire lift of the valve, valve at any point n, and A2=A1I3- been Referring again to Fig. 5. It has that found, by the calculus ofv variations,

the minimum closing surface to close an annular opening between two parallel circles not in the same plane, is formed by revolving catenary` NOR around CP as an axis. It isnot deemed necessary to develop the mathematical computations for this proposition because they are known and exceedingly complex and also because, in a case of comparatively small valves, such as would be used in carbureters, the area of the catenoid is so very nearly equal to that of the surface of the frustum of the cone between thetwo cireles that the latter area has been used in the subsequent computations. Such procedure produces sufficient" accuracy for ordinary purposes and is proper in View of the fact that the slight errors due thereto are modiied by the variables (o) and (d) already referred to and which must be worked out, for eXtreme accuracyby some experimental process such as I shall hereafter describe.

Referring again to Fig. 3, let Sra point on any circle of the valve arallel to the plane of the orifice, h: Szthe slant height of the opening between orifice and valve,` rzthe'radius of the orifice, azth-e angle, which (OS) the radius of the mid circumference of the frustum ofthe cone formed by revolving (OS) about (MN).

Then nr2=27zrnh, 2Mb-Moos. a.

Let hzcrza constant multiplied by 7.

rlhen cos. (L C,

Substituting a series of values for c above, we get the following table:

Fig. 3 is plotted from this table.

Referring now to Fig. 3, let the total lift ORO20 be divided into twenty equal steps. The area of a 12 inch circle is 113.1004- square inches. Call this (A). At position 2 (Fig. 3) the area of the opening must 2 20 inches.y At position 4, the area will be equal and this is equal to 11.31 square equal to gi, at the position 5, 9%-, etc.

Starting at position 2, and assuming a makes with (NO), rn:

values for h until 1r(d-h cos. a)h= 11.310.

When a proper h has been found for each of a. series of values of a, the curve (2 2) shown in Fig. 3 of the drawings, can be drawn. Passing to position 4 and follow ing the saine procedure, the curve (4--4) can be drawn in the same way and similar curves for as many other positions as may be desired. The figures for these several curves, assuming the orifice diameter OLOR to be 12 inches, are contained in the following table Pos1' A a h Cos a h cos a Mid' Mid Cotxeld tion. diam. circum. plllx 11.31 o .sos 1 .aos 11.692 36.7 11.31 10 308 985 302 11. 697 36. 7 11. 30 20 307 94 2885 11. 71 36. 8 11. 30 30 3065 866 265 11. 735 36. 86 11. 30 40 306 766 235 11. 765 36. 9,61 11. 30 4.... 22. 62 0 635 635 11. 635 35. 702 2 2. 65 10 634 985 624 11. 376 35. 74 22. 68 20 631 94 594 11. 466 35. 814 22. 61 30 628 866 544 11. 456 35. 990 22. 6 40 626 766 480 11. 52 36. 190 22. 62 6 33. 93 0 .980 1 980 11. 02 34. 621 33. 92 10 978 985 972 11. 028 34. 646 33. 91 20 973 944 9125 11. 0875 34. 831 33. 91 30 967 866 836 11. 164 35. 079 33. 90 40 958 766 734 11. 266 35. 393 33. 93 5o .94s 643 61o 11.39 35. 783 33. 93 's 45. 2s o 1.35 i 1 35 10.65 33.453 45.3

10 1. 752 .985 1 721 10. 279 32. 29 56. 6 20 1. 7325 94 1 63 10. 37 32. 578 56. 5 30 1. 710 866 1 47 10. 53 33. 08 56. 6 40 1. 68 766 1 304 10. 696 33. 603 56. 55 60 1. 605 5 8025 11. 1975 3o. 178 56. 55 12... 67. 86 0 2. 20 l 2. 20 9. 80 30. 7876i 67. S0

10 2.19 .985 2.155 e. 845 "10.93 1 67. s 20 2. 165 94 2. 035 9. 965 31. 300 67. 8 30 2. 12 866 1. 835 10.165 31. 937 67. 78 4o 2. 08 .w66 1.614 1o aso 32. 60s c7. s 60. 1. 96 50 98 11 02 34. 620 67. 85 14... 79. 17 0 2. 72 1 2. 72 9. 28 29. V177 79.18 10 2. 70 985 2. 66 9. 34 29. 34 79. 20 20 2. 65 94 2. 49 9. 51 29. 88 79. 10 30 2. 585 866 2. 238 9. 762 30. 668 79. 12 40 2. 50 766 1. 914 10. 086 31. 686 79. 20 50 2. 42 643 1. 555 10. 445 32. 814 79. 20 70 2. 24 342 766 1l. 234 292 79. 15 16... 90. 48 0 3. 32 1 3. 32 8. G7 27. 24 90. 5 10 3. 28 985 3. 22 8. 78 27. 5S 90. 4 20 3. 20 94 3. 01 8. 99 28. 24 90. 4 30 3. 09 866 2. 67 9. 33 29. 31 90. 6 40 2. 96 766 2. 27 9. 72 30. 56 90. 50 50 2. S3 643 1. 810 10.19 32. 01 90. 6 17... 96. 135 0 3. 68 1 3. 68 8. 32 26. 14 96. 2 10 3. 64 985 3. 580 8. 42 26. 45 06. 5 20 3. 52 94 3. 31 8. 69 27. 30 96. 15 30 3. 39 866 2. 97 9. 03 28. 37 96. 18 40 43. 22 766 2. 48 9. 52 29. 90 96. 20 50 3. 085 643 1. 97 10. 03 31. 15 96. 10 60 2. 91 50 l. 45' 10. 545 33. 13 96. 2 18..: 101. 79 0 4. 10 1 4. 10 7. 90 24. 81 101. 5 20 3. 89 94 3. 66 8. 34 26. 2 101. 7 30 3. 68 866 3.185 S. S15 27. 69 101. 8 40 3. 45 766 2. 63 9. 37 29. 44 101. 6 50 3. 26 64?- 2. 08 9. 92 '31. 17 101. 5 60 3.12 500 1. 60 10. 40 32. 70 101. 8 19..... 107.445 0 4.66 1 4.66 7.34 23l09` 107.45

When the several curves, above described, have been drawn, it will be readily apparent series of values for a, take different trial lifts when the total lift of the valve is equal to the orifice diameter. Following the same theory, the full line ORN2 in Fig. 4 will be the generating line for the valve when the lift of the valve is equal to one-half of the orifice diameter.

Referring again to Fig. 3, it will be seen that at the line T20, which indicates the plane w-here the curvature of the generating line changes, the shape of the valve below this line does not alter the effective size of the orifice and therefore the nose or tip of the valve may be given any shape so long as it lies above the curve T20N but it is advisable to follow close to the-line TZON in order to reduce the possibility of the production of eddy currents in the issuing streaml of gas.

For many practical purposes, where extreme accuracy is not necessary, the parabola OLBN might be used as the generating line for the valve, for an examination of Fig. 3 of the drawings showsthat for an orifice of Vthe size shown there will be a gradual increase of error as the valve is lifted from its closing position, the later opening steps failing to add a complete increment unit to the effective area. A closer approximation may be obtained by using the parabola AOLAP which, as seen in Fig. 3, lies a little inside the true curve at about the middle of the length and lies a little outside of the true curve at the point of the valve. It will be readily understood, of course, that where the valve is small, the error is not so" apparent but where such a valve is used, it should' be remembered that the total outflow is small and that therefore Where Athe relation between orifice diameter and valve lift remain the same, the error is as great in one size of valve as another, so that the true curve, 'as determined in the manner set forth above should be followed as closely as possible. It should also be noticed that where the lift of the valve is less than the orifice diameter, the difference between approximating parabolas and the true generating line is muchI more marked. This is clearly shown in Fig. 4, where the dotted lines show approximating parabolas.

As I have already stated, the forms of valve Vshown in Figs. 3 and 4 and other valves determined by the table given above, are obtained by neglecting certain variables which are more readily determined experi mentally than mathematically and-.where extreme accuracy is desired, should be obtained experimentally. For this purpose, I

have found it advisable to provide an ap- I aratus illustrated diagrammatically in Fig. of the drawings. In this test'l apparatus, the air pump has a suiicient capacity to maintain a vacuum of l1 1/2 inches of water above the valve in the carbureter, with the auxiliary valve wide open. This vacuum is measured by means yof a water manometer attached to the body of the carbureter just below the throttle, as indicated in Fig. 7. The -carbureter body is soldered into an intake pipe in which an anemometer .is placed so that all of the,v air passing through the valve orifice must also pass through the anemometer. The position of the test valve is measured by means of a micromometer valve stem which, in my test appara-tus, had 40 threads to t-he inch. This stem is threaded through the body casting of the carbureter and capped by a disk graduated into twenty-five equal parts so that the exact position of the ,valve relative to the orifice may be accurately determined. The anemometer used should be, and was, provided with. an accurate calibration curve giving exact velocityin feet per minute corresponding to each reading of the instru. ment. The volume of air passing through the valve will be exactly proportional to the velocity through the anemometer. If now the valve be set in a number of different positions and the air passing through each orifice in a given time be accurately determined when a constant vacuum is maintained in the carbureter, the lift-delivery curve should be a straight line. Any vari-v ation from a straight line will readily indicate the exact valve position which, by reason of/ some local disturbance, variesfrom the theoretically proper shape and by changing the shape of the valve at this point, thus altering the valve generating line, the exact valve form for the particular apparatus may be determined, it being always remembered that the desired valve form is one which will give substantially equal increments of effective orifice area for equal valve lifts no matter where, in the total valve movement, the particular valve lift is maole.

In testing the fuel needle, the fuel is supplied to the carbureter from a tank balanced on delicate scales. With the fuel tank a little too .heavy to balance, the pump is started and regulated to give the desired vacuum at the carbureter. The instantthe tank comes to abalance and starts to rise, a stop watch is started and a known weight is removed from the weight pan and the time that elapses before the fuel tank balances again is recorded. The lift-delivery curve is then drawn foiI the fuel needle and the needle corrected in ,shape until it gives 'a straight delivery curve.

I have considered it advisable lto enter into determining nwo-,525

considerable detail' as tothe exact manner of the proper shape of the proportioning valves because, while I am aware that many designers of carburetersand other similar proportioning devices have recognized the desirability of obtainingruniformity of proportioningl of mixtures throughout the range of appartaus, yet so far as I am aware, no such'apparatus having the possibility of adjustment to vary the proportion has ever 'heretofore been produced because of a failure, the'part' of prior designers.- to recognize'y the fact that ordinary forms of valves common in use for throttling purposes, are wholly incapable-of adding uniform increments of effective oriice area for uniform movements away from the closing position throughout the range of movement of the valve.

Attention has already been directed to the primary air passage l'whi'ch is always gpen.

believe that in practice the best results can be obtained with such an arrangement and when it is provided it is, of course, necessary to provide some arrangement by which the air volume through this passage will always receive' its proportionate amount of'ftuell In the form .shown inthe drawings all4 ofthe fuel' is first delivered to the particular quantity of air passing through the primary air passage, to' be subsequently mixed with the other air which is admitted' by the movement of valve 14, but, no matter what the arrangement may be', the particular quantity of air passing through the primary passage,

` as comparedv with the quantity of air passing through the passage controlledt by valve 14, should receive its exact quota ofy fuel. In order to accomplish this result, in the form of apparatus'shown in Fig; 1, the upper end of valve stem 15 is vertically -adjust'adile being threaded4 upon the main valve stem.I so that the free end of lever 16'y may, by anadjust-ment ofv thev upperend2v of stem 1'5, be moved upwardlyan amount which, compared with the totaly maximumv lift' of the lever (l e., the total maximum lift of valve 14 from closed' position to wide open) will be in the same ratio as exists between the total effective area of the primary air passage andthe maximum effective areaV of the opening controlled by valve 14'.-

It will be readily understood that many different forms of mechanisms maybe pro- 'vided to obtain the desired proportional movements of the two valves and that' the structure shownin Fig.` 1 is selected, not because it is the only structure, but because itis one used in the practical` development of my'invention. In Fig. 8 I show diagrammatically another construction' for accomplishing the same purpose. In this construction a swinging' air lvalve 50' is` provided with a cam 51 operating upon a shoe 52 which engages a lever` 53. Lever 55 carries a longitudinally adjustable finger 54 operating upon a lever 55 which carries a cam 56- operating upon the stem of valve 57. In order to determine the shapes of the-cams used inV this construction, the maximum -movement of valve 50 should be divided into equal area increments and the same should be done for the maximum movement of valve 57 and when this has been done the exact conguration of the necessary cams may be determined according to the usual manner of laying out cams for the accomplishment of any'particu'lar and desired movement.

I'n. the form shown in Fig. 9, the stem of valve 60 is provided 'with a cam plate 6l pivoted at' 62'upon the stem of the valve and provided at" its other end' with a clamping nut 63 by means of which the angle ofinclination' of the cam 61 maybe varied" The cam? 61 operates directly upon a pin 64, conveniently adj ustably held by clamp 65, upon the stem of valve 66. In this form also the valves must be so formed, as compared with the or-ices-v controlled thereby, as to give 'equalareaincrements for 'equal lifts of the valve'l Ift maybe well here to state that the ffliflt wot the valve isint'ended hereto mean a= 'relative movement' between theV valve and the' orifice controlled thereby,

In- Fig. 10 the valve 7 O`is connected to a lever 71 having'a shiftable fulcrum 72 and lever 71 carries afcam plate 73 operating upon theastem of' valve 74. W'hatever form .of valvev actuating means is provided, it

must be such, as comparedI with the throttling value'oftlie valve that, when any particular'to'tals movement ofthe valve is settied upon, then a certain' defined lift4 of the valve will 4alfvvays give acertain increment of' e'ecti've area no matterwhat portion ofthe total'- stroke the particular lift may be. p

I claim as my invention;

1;. A- carbureter comprising a'n air passage, anl antomatically-opetatmg, inwardlyopeningy air valve' for controlling the inlet area of'y the air passage 'a fuel passage delivering into the air passage on the vacuum. side of the air. valve, a fuel valve vfor controlling the outlet area of the fuel passage, and intermediate connections between the air valve-andI the fuelvalve whereby minute arithmetically-varyingeEective-delivery inv l'etl areas of the air passage will be accomp'a'ni'e'dby corresponding minute arithmeticall'y-varying effective-delivery outletareas of the fuel passage, said intermediate connections comprising an adjustable member whereby the rat-io between the movement of the" air valve and the fuel valve may be varied.

2; A carbureter comprising an air passage, an automatically-operating, inwardlyopening valve for controlling the inlet area of the airzmss'age, a fuel passage delivering -tive area of the air passage,

the fuel valve may be variably adjusted, one

of said valves comprising a paraboloid 3. A carbureter comprising an air passage, an air valve for controlling the inlet area of the air passage, said valve being operable inwardly by suction, means normally moving said valve toward closing position, a fuel passage delivering into the air passage on the vacuum side of the air valve, a fuel valve for controlling the outlet area of the fuel passage, and intermediate connections between the air valve and the fuel valve whereby minute arithmetically varying inlet areas of the air passage will be accompanied by corresponding minute arithmetically varying outlet areas of the fuel passage, said intermediate connections comprising anadjustable member whereby theratio between the movements of the air valve'and the fuel valve may'l be varied.

4. A carbureter comprising an air passage, an automatic suction-controlled throttling valve associating with said passage and havin a form such that equal minute successive if'ts of the valve will add successive equal minute increments to the effeca fuel passage, a throttling valve associating withsaid passage and having a form such that equal minute successive lifts of the valve will add successive equal minute increments to the effective area of the fuel passage, and means for simultaneously operating said valves, said operating means comprising an adjustable member by which the total lift of on?jl valve relative to the other may be varie 5. A carbureter comprising an air passage, an automatically-operating, inwardlyopening air valve for controlling the inlet area of the air passage, a fuel passage delivering into the air passage on the vacuum side of the air valve, a fuel valve of the coaxial-plug type for controlling the outlet area of the fuel passage, and intermediate connections between the air valve and the fuel valve whereby simple arithmeticallyvarying effective-delivery inlet areas of the 'air passage will be accompanied by, corresponding simple arithmetically-varying effective-delivery outlet areas of the fuel passage, said intermediate connections comprising an adjustable membertwhereby the controlling said air ratio between the movement of the air valve and the fuel valve may be varied.

6, A proportioning mixer comprising two flow? passages, two throttling valves associated with said flow passages, one of said valves having a normalr full stroke movement, intermediate adjustable connections between said two valves whereby movement of the full stroke valve will produce 4'different desired proportionate movements of the other valve, and the said other valve being of the coaxial-plug type and having such form relative to the orice which it controls that equal minute lifts of said valve, throughout its range of movement, will give substantially equal minute l outlet increments.

7 A carbureter, comprising an air passage, an automatic suction-controlled valve controlling said air passage and .having a normal maximum passagecontrolling throw, a fuel passage, a controlling valve of the coaxial-plug type for the fuel passage and so formed, relative to the fuel passage that equal lifts of the valve will add equal increments to the effective area of the fuel passage, and adjustable connections between the air valve andfuel valve for varying the maximum throw of the fuel valve relative to the throw of the air valve. 95

8. A carbureter, comprising an air passage, an automatic suction-controlled valve passage and having a normal maximum passage-controlling throw,

a fuel passage, a controlling valve for the 100 fuel passage and so formed, relative tothe fuel passage that equal minute lifts of the valve will add equal minute incrementsto the-e'ec'tive area of the fuel passage, and

.adjustableconnections between the air valve and fuel. valve for varying the throw of the fuel valve' relative to the throw of the air valve. l

9. Ina carbureter, an air passage, a suction-controlled valve controlling said air passage and having .a normal maximum throw, said valve being of the coaxial-plug type, a fuel passage, a valve of the coaxialplug type controlling said fuel passage and so formed relative to the fuel passage that 1,15 equal lifts of the val-ve will add equal increments to the effective area. of the fuel passage, a lever connected to the air valve and moved thereby, a lever connected'to the fuel valve to move the same, and a movable finger arranged between the two levers to transmit proportionately the movement of the air valve tothe fuel-valve.

l0. In a carbureter, an air passage, a suction-controlled valve controlling said air .1"25 passage and having a normal maximumv throw, a fuel passage, a valve of the coaxialplug type controlling. said fuel passage and so formed relative to the fuel passage that equal lifts of the valve will add equal increments to the effective area of the fuel pas- 12. In a carbureter, an air passage, a sucsage, a lever connected to the vair valve and tion-controlled valve controllingl said air vmoved thereby, a lever connected tothe fuel passage and having a normal maximum valve to move the same, and a movable throw, a fuel passage, a valve controlling finger arranged between the two levers to said fuel passage and so formed relative to transmit proportionately the movement of lthe fuel passage that equal lifts of the valve the air valve to the fuel valve. will add equal increments to the effective' 11. In a carbureter, an air passage, a'sucarea of the fuel passage, a lever connected tion-controlled valve controlling said air to the air valve and moved '.therebya lever passage and having a normal maximum connected to the fuel valve to move the same,

throw, said valve being of the coaxial-plug and a movable finger arranged betweenthe type, a fuel passage, a valve controlling two levers to transmit proportionately the said fuel passage and so formed relative to movement of the air valve tothe fuel valve. the fuel passage that equal lifts of the valve In witness whereof, I have hereunto set will add equal increments to the effective my hand at La Fayette, Indiana, this fourth area of the fuel passage, a lever connected day of January, A. D. one thousand nine to the air' valve and moved thereby, a lever` hundred and thirteen.

connected to the fuel valve to move the same, HOMER N. MOTSINGER. and a movable finger arranged between the Witnesses:

two' levers to transmit proportionately the O. C. BERRY, movement of the air valve to the fuel valve. B. L. ROGERS. 

